Page 41 - waterfall Issue 12 2021

ouR LiVing

dEsERTs

By James Clarke
L iving, as most of us do, on the high of surviving the searing temperatures

inland plateau of Southern Africa,
and the rainless months.
what do we consider a good rainfall?
A summer storm can often bring Lovegrove has forebodings regarding
20mm of rain in an hour. That’s good. We often climate change and its potential effects
experience twice that, even three times more. on such a finely tuned ecosystem. He
is worried because, during the years he
But consider this: in the dry half of South has worked in the deserts, retrograde
Africa, 20mm is as much as people changes have already manifested.
expect in a year. Some, in the far west,
record as little as 5mm a year. He writes for fellow scientists as well as for
students and for the growing mass of people
How do the animals and plants survive? interested in natural history. He writes of the
Call it evolutionary ingenuity. Some, for amazing adaptations shown by creatures in
instance, tap the nightly fogs coming order to survive in desiccated environments.
in from the cold Atlantic. The fogs roll
eastwards only to evaporate at sunrise. One of the most astonishing adaptations
There are beetles that cling upside down he mentions concerns the Namaqua
to leaf stems allowing the fog to condense sandgrouse. Although its chicks are able
on the surfaces of their hard-shelled outer to run around and feed on seeds from the
wings. The droplets accumulate and trickle day they hatch, they cannot drink. They
down to their heads and mouth parts. can’t drink because they can’t fly and the
nearest water might be 50 to 60km away.
There’s a marvellous picture of weevils doing The male sandgrouse then has to carry
this in Barry Lovegrove’s The Living Deserts of water to them. It sits in the water fluffing out
Southern Africa. The book is a greatly expanded its feathers to absorb as much as possible
revision of his 1993 bestseller of the same title. – these feathers can hold more water per
unit weight than a kitchen sponge. Daily
Lovegrove, an evolutionary physiologist, it flies back to its young, which take the
writes with an easy style and is unafraid of wet feathers in their beaks and strip the
emotion or offering forthright views. He writes water. very little water is lost during the
as a lover of desert life and describes how our return flights to the nest because the bird
barren wastes teem with life just as varied and holds the soaked feathers against its body
species-rich as our coastal forests. The diversity effectively reducing the airflow over them.
of creatures in these arid regions varies from
ants to elephants. The birdlife is amazing and Southern Africa has nine biomes, ranging from
there are thousands of species of plants – four desert biomes in the west to the greener
hundreds found nowhere else in the world. wetter biomes east of here. Yet, whether
rainforest or arid land, each biome is rich in
Each living thing has its ingenious way its variety of creatures and plants. Deserts

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